Inflammation normally occurs in response to infection by invading micro-organisms. This inflammatory response is beneficial because it is an important part in localizing the infecting agent for removal by the immune system. However, in autoimmunity there is no infection, yet severe inflammation is present. The inflammation in this case, referred to as aseptic chronic inflammation, is detrimental since it destroys normal tissues. The results of this aseptic inflammation are life-altering and in some cases life-threatening. Moreover, as with acute inflammation, this process is mediated by immune cells, including T-cells.
A major concern for modern medicine is how to control aseptic, chronic inflammation (ACI) such as that which occurs during autoimmune diseases, as well as how to control acute inflammation resulting from trauma. Inflammation, both chronic and acute, leads to tissue degeneration and eventual loss of function of major organs. ACI is not limited to a single disease, but is instrumental in numerous autoimmune diseases including, but not limited to type 1 diabetes, multiple sclerosis, systemic lupus erythematosa, rheumatoid arthritis, Crohn's disease, inflammatory bowel disease, chronic obstructive pulmonary disease including types of autoimmune asthma, atherosclerosis, vasculitis, hypertension, thyroiditis including Hashimoto's and Graves diseases, primary biliary cirrhosis, Paget's disease, Addison's disease, acute respiratory distress syndrome, acute lung injury, and ACI associated with organ transplantation.
Autoimmune disorders are classified into two types: organ-specific (directed mainly at one organ) and non-organ-specific (widely spread throughout the body). Examples of organ-specific autoimmune disorders are insulin-dependent Type 1 diabetes which affects the pancreas; Hashimoto's thyroiditis and Graves' disease, which affect the thyroid gland; pernicious anemia, which affects the blood; Addison's disease, which affects the adrenal glands; chronic active hepatitis, which affects the live; myasthenia gravis which affects the muscle; and multiple sclerosis, which affects tissue of the nervous system. An example of a non-organ-specific autoimmune disorders is rheumatoid arthritis. Autoimmune diseases are often chronic, debilitating, and life-threatening. The National Institutes of Health (NIH) estimates that up to 23.5 million Americans suffer from autoimmune disease and that the prevalence is rising. It has been estimated that autoimmune diseases are among the ten leading causes of death among women in all age groups up to 65 years.
Acute inflammation, as observed during trauma or sepsis, is also immune cell mediated. While all of the molecular mediators in this process have not yet been identified, a prominent role for T cells, macrophages/monocytes, neutrophils etc., is strongly implicated. Therefore a means to modulate these cell types would necessarily control the inflammatory response.
A unique T cell subset has been shown to be instrumental in the development of autoimmune disease. These cells are phenotypically characterized as CD4loCD40+ (Waid, D. M., G. M. Vaitaitis, and J. Wagner, D. H. 2004. European Journal of Immunology 34:1488; Vaitaitis, G. M., M. Poulin, R. J. Sanderson, K. J. Haskins, and D. H. Wagner Jr. 2003. Cutting Edge, J. Immunol. 170:3455; Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins 2002. Proc Natl Acad Sci USA 99:3782; Wagner, D. H., Jr., E. Newell, R. Sanderson, J. H. Freed, and M. K. Newell. 1999. International Journal of Molecular Medicine 4:231), and are referred to as Th40 cells. CD40 expression typically is associated with antigen presenting cells and the majority of prior art describes CD40 as being expressed on B cells, macrophages, monocytes etc. However CD40 proteins are also expressed on T cells (Waid, D. M., G. M. Vaitaitis, and J. Wagner, D. H. 2004. European Journal of Immunology 34/1488; Vaitaitis, G. M., M. Poulin, R. J. Sanderson, K. J. Haskins, and D. H. Wagner Jr. 2003. Cutting Edge, J. Immunol. 170-3455; Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins 2002. Proc Natl Acad Sci USA 99:3782; Wagner, D. H., Jr., E. Newell, R. Sanderson, J. H. Freed, and M. K. Newell. 1999. International Journal of Molecular Medicine 4:231; Bourgeois, C., B. Rocha, and C. Tanchot. 2002. Science 297:2060; Fanslow, W. C., K. N. Clifford, M. Seaman, M. R. Alderson, M. K. Spriggs, R. J. Armitage, and F. Ramsdell. 1994. Journal of Immunology 152:4262; Ramsdell, F., M. S. Seaman, K. N. Clifford, and W. C. Fanslow. 1994. Journal of Immunology 152:2190; Grabstein, K. H., C. R. Maliszewski, K. Shanebeck, T. A. Sato, M. K. Spriggs, W. C. Fanslow, and R. J. Armitage. 1993. Journal of Immunology 150:3141; Armitage, R. J., C. R. Maliszewski, M. R. Alderson, K. H. Grabstein, M. K. Spriggs, and W. C. Fanslow. 1993. Seminars in Immunology 5:401; Cooper, C. J., G. L. Turk, M. Sun, A. G. Farr, and P. J. Fink. 2004. J Immunol 173:6532). While Th40 cells comprise a proportion of the peripheral CD4+ compartment in naïve, non-autoimmune mice (Waid, D. M., G. M. Vaitaitis, and J. Wagner, D. H. 2004. European Journal of Immunology 34:1488; Wagner, D. H., Jr., E. Newell, R. Sanderson, J. H. Freed, and M. K. Newell. 1999. International Journal of Molecular Medicine 4:231), and in humans (Waid. D. M, R. J. Wagner, A. Putnam, G. M. Vaitaitis, N. D. Pennock, D. C. Calverley, P. Gottlieb, and D. H. Wagner, Jr. 2007. Clin Immunol 124:138), this proportion is drastically expanded to as much as 50% of the CD4+ compartment in autoimmune prone mice (Waid, D. M., G. M. Vaitaitis, and J. Wagner. 2004. European Journal of Immunology 34:1488; Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins 2002. Proc Natl Acad Sci USA 99:3782; Wagner, D. H., Jr., E. Newell, R. Sanderson, J. H. Freed, and M. K. Newell. 1999. International Journal of Molecular Medicine 4:231) and humans (Waid. D. M, R. J. Wagner, A. Putnam, G. M. Vaitaitis, N. D. Pennock, D. C. Calverley, P. Gottlieb, and D. H. Wagner, Jr. 2007. Clin Immunol 124:138). These T cells do not express early activation markers and occur in the naïve phenotype of non-challenged mice. In diabetic NOD mice, Th40 cells occur at exaggerated levels in spleen, lymph nodes and the pancreas, even prior to diabetes onset (Waid, D. M., G. M. Vaitaitis, and J. Wagner, D. H. 2004. European Journal of Immunology 34:1488; Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins. 2002. Proc Natl Acad Sci USA 99:3782). An elevated number and percentage of these T cells is seen in peripheral blood of type 1 diabetic patients when compared to non-autoimmune controls and type 2 diabetic patients (Waid. D. M, R. J. Wagner, A. Putnam, G. M. Vaitaitis, N. D. Pennock, D. C. Calverley, P. Gottlieb, and D. H. Wagner, Jr. 2007. Clin Immunol 124:138).
The observed increase in Th40 cells could mean that those T cells are antigen responsive or that CD40 expression is activation induced. Furthermore, several diabetogenic T cell clones are CD40+
(Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins. 2002. Proc Natl Acad Sci USA 99:3782). Purified primary Th40 cells from diabetic NOD mice and from pre-diabetic NOD (12-weeks of age) mice successfully transfer type 1 diabetes to NOD.scid recipients, directly demonstrating pathogenicity of that T cell subset (Waid, D. M., G. M. Vaitaitis, and J. Wagner, D. H. 2004. European Journal of Immunology 34:1488; Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins. 2002. Proc Natl Acad Sci USA 99:3782). It has been shown that Th40 cells infiltrate islet beta cells destroying insulin production thus suggesting islet antigen specificity (Waid, D. M., G. M. Vaitaitis, and J. Wagner, D. H. 2004. European Journal of Immunology 34:1488; Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins 2002. Proc Natl Acad Sci USA 99:3782). It has also been shown that Th40 cells are required for diabetes transfer. Peripheral (spleen and regional lymph node) T cells that were CD40 depleted, then CD25, Treg, depleted were not capable of transferring diabetes to Scid recipients. Even though Tregs were removed, if the autoaggressive CD40+ T cells subset is absent, disease transfer does not occur.
While Th40 cells are important in the development of autoimmunity, another important factor is expression of the CD40-Ligand, CD154. CD154 is temporally induced on activated T cells in response to CD3/TCR stimulation (Lederman, S., M. Yellin, A. Krichevsky, J. Belko, J. Lee, and L. Chess. 1992. Journal of Experimental Medicine 175:1091). CD154 expression has also been demonstrated on platelets, monocytes, basophils, eosinophils, dendritic cells, fibroblasts, smooth muscle, and endothelial cells (Russo, S., B. Bussolati, I. Deambrosis, F. Mariano, and G. Camussi, 2003. J Immunol 171:5489; Stumpf, C., C. Lehner, S. Eskafi, D. Raaz, A. Yilmaz, S. Ropers, A. Schmeisser, J. Ludwig, W. G. Daniel, and C. D. Garlichs. 2003. Eur J Heart Fail 5:629; Schonbeck, U., and P. Libby. 2001. Cell Mol Life Sci 58:4). CD154 is a member of the tumor necrosis factor (TNF) super-family and a soluble form of CD154 (sCD154) has been described (Russo, S., B. Bussolati, I. Deambrosis, F. Mariano, and G. Camussi. 2003. J Immunol 171:5489; Stumpf, C., C. Lehner, S. Eskafi, D. Raaz, A. Yilmaz, S. Ropers, A. Schmeisser, J. Ludwig, W. G. Daniel, and C. D. Garlichs. 2003. Eur J Heart Fail 5:629; Toubi, E. and Y. Shoenfeld. 2004 Autoimmunity 37:457). Therefore, sCD154 may act like a cytokine (Stumpf, C., C. Lehner, S. Eskafi, D. Raaz, A. Yilmaz, S. Ropers, A. Schmeisser, J. Ludwig, W. G. Daniel, and C. D. Garlichs. 2003. Eur J Heart Fail 5:629). Even though CD154 has not been genetically linked in T1D studies, sCD154 is significantly elevated in T1D and may play a role in the disease process (Varo, N., D. Vicent, P. Libby, R. Nuzzo, A. L. Calle-Pascual, M. R. Bernal, A. Fernandez-Cruz, A. Veves, P. Jarolim, J. J. Varo, A. Goldfine, E. Horton, and U. Schonbeck. 2003. Circulation 107:2664; Cipollone, F., F. Chiarelli, G. Davi, C. Ferri, G. Desideri, M. Fazia, A. lezzi, F. Santilli, B. Pini, C. Cuccurullo, S. Tumini, A. Del Ponte, A. Santucci, F. Cuccurullo, and A. Mezzetti. 2005. Diabetologia 48:1216; Devaraj, S., N. Graser, S. Griffen, J. Wang-Polagruto, E. Miguelino, and I. halal. 2006. Diabetes 55:774). The importance of CD40-CD154 interaction in autoimmunity has been established (Wagner, D. H., Jr., G. Vaitaitis, R. Sanderson, M. Poulin, C. Dobbs, and K. Haskins. 2002. Proc Natl Acad Sci USA 99:3782; Kobata, T., M. Azuma, H. Yagita, and K. Okumura. 2000. Rev. Immunogenet 2:74; Homann, D., A. Jahreis, T. Wolfe, A. Hughes, B. Coon, M. J. van Stipdonk, K. R. Prilliman, S. P. Schoenberger, and M. G. von Herrath. 2002. Immunity 16:403; Goodnow, C. C. 2001. Lancet 357:2115; Balasa, B., T. Krahl, G. Patstone, J. Lee, R. Tisch, H. O. McDevitt, and N. Sarvetnick. 1997. Journal of Immunology 159:4620). Blocking CD40-CD154 interaction prevents collagen induced arthritis (Durie, F. H., R. A. Fava, T. M. Foy, A. Aruffo, J. A. Ledbetter, and R. J. Noelle. 1993. Science 281:1328) experimental autoimmune encephalitis (Howard, L. M., and S. D. Miller. 2004. Autoimmunity 37:411), prostatitis (Grossman, M. E., E. Davila, and E. Celis. 2001. J Immunother 24:237), and importantly type 1 diabetes in the NOD mouse model (Balasa, B., T. Krahl, G. Patstone, J. Lee, R. Tisch, H. O. McDevitt, and N. Sarvetnick. 1997. Journal of Immunology 159:4620). In the diabetes model it was essential to administer a CD154 blocking antibody to NOD mice at 3-weeks of age; at 9-weeks, blocking antibodies had no effect on diabetes prevention (Balasa, B., T. Krahl, G. Patstone, J. Lee, R. Tisch, H. O. McDevitt, and N. Sarvetnick. 1997. Journal of Immunology 159:4620).
Previous work has also demonstrated that the Th40 cell subset induces RAG1 and RAG2 transcription, translation and nuclear translocation (Vaitaitis, G. M., M. Poulin, R. J. Sanderson, K. J. Haskins, and D. H. Wagner Jr. 2003. Cutting Edge, J. Immunol. 170:3455) when CD40 is engaged. CD3 engagement does not induce RAG1 or RAG2 in T cells (Vaitaitis, G. M., M. Poulin, R. J. Sanderson, K. J. Haskins, and D. H. Wagner Jr. 2003. Cutting Edge, J. Immunol. 170:3455). Subsequent to RAG1/RAG2 induction, CD40-mediated TCR revision occurs in peripheral T cells (Vaitaitis, G. M., M. Poulin, R. J. Sanderson, K. J. Haskins, and D. H. Wagner Jr. 2003. Cutting Edge, J. Immunol. 170:3455). CD40 induction of TCR revision is RAG dependent. T cells isolated from a TCR-Tg mouse undergo TCR revision when CD40 engaged, but T cells from the TCR-Tg.RAG−/− mouse do not TCR revise when CD40 engaged (Wagner, D. H., Jr., E. Newell, R. Sanderson, J. H. Freed, and M. K. Newell. 1999. International Journal of Molecular Medicine 4:231).
Multiple treatment options have been put forward to address and control both chronic and acute inflammation. Many approaches use non-steroidal anti-inflammatory drugs (NSAIDS) that attack the production of leukotrienes and prostaglandins, cellular products that cause localized inflammation. Other approaches use more powerful immunosuppressant drugs such as cyclophosphamide, methotrexate and azathioprine that suppress the immune response and stop the progression of the disease. Still other treatments involve the use of monoclonal antibodies designed to alter the immune responses to self-tissues, as occurs during autoimmune diseases. However, all of these treatments often have severe, long-term side effects.
Thus, there exists a need in the art for safer and more effective methods for treatment and prevention of autoimmune diseases. The present invention addresses this need by describing a novel method for treatment of autoimmune diseases.